Phonograph



J. A. LUNDEN.

PHONOGRAPH.

APPLICATION FILED MAY 10, 1920.

Patented Nov. 28, 1922.

INVENTOR. JbH/VA L u/vos/v. 6 @we W1 TNESS: Z

A TTORNE Y.

Patented Nov. 28, 1922 UNITED STATES PATENT OFFICE.

JOHN A. LUNDEN, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO ROBERT C.

' i DANLY, OE CHICAGO, ILLINOIS.

PHONOGRAPH.

Application filed Kay 10, 1920.

To all whom it may concern:

Be it known that I, JOHN A. LUNDEN, a citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, haveinvented a new and useful Improvement in Phonographs, of which thefollowing is a specification.

My invention relates to an improved phonograph construction by which thevibrations recorded on a record disc may be communicated without loss ofintensity and tonal characteristics to'an amplifying device of novelconstruction by which the characteristics are preserved and body andvolume are imparted to the tone.

The amplifying device is preferably provided with a plurality oftransverse part1- tions causin the sound waves to pass around theiredges 1n wave like fashion towards the free or open end of theamplifying device, so that the parts of the amplifying dev1ce arebrought into intimate association with and vibrated by the sound waves.More specifically my amplifying device consists of an enclosing casingof tubular or conical formation having transverse partition ringssecured to its inner surface at intervals, between which discs ofsmaller diameter than the inner diameter of the shell or casing aremounted upon a rod or reed of resilient ma terial, preferabl wood, whichrod is centrally supported by being secured to the sound receiving endof the amplifying device.

My invention will best' be understood by reference to the accompanyingdrawings showing a preferred embodiment thereof in which-- The figure isa side elevation of a part of my device with the remaining parts invertical sectional view, the parts being in assembled relation and readyfor use.

Referring to the drawing, 10 designates the annular wall of a phonographsound box having the usual lateral extension 11 for the attachment ofthe stylus mounting of the instrument.

12 designates the sound box diaphragm, secured in place by holding rings13 of resilient material, while 14 designates the back wall of the soundbox formed with a central aperture 15 communicating with the bore of atubular elbow 16 forming a fixed part of said back wall.

17 designates a companion tubular elbow Serial No. 380,068.

attached to the aforesaid elbow 16 and having the axis of its tubularportion or branch 18 in parallel relation with the axis of the annularwall 10 of the sound box.

In the form of stylus mounting shown in the drawing, 20 designates astrip of spring material rigidly secured at its respective ends to thesound box extension 11 aforesaid, with its central portion carrying astud or post 21 having its free end formed with a receiving socket inwhich the needle or stylus 22 is secured by a set screw 23 or otherusual means.

24 designates an arm fixedly attached to the post 21 and extendinglaterally therefrom towards the center of the sound box, with its freeend connected to the diaphragm 12 by a screw or other usual fasteningmeans.

The tubular extension 18 has its axis in-- clined to the surface of therecord 26 when supportedon the turn table 27 of the machine, atsubstantially the angle of most effective engagement between the needleor stylus and the record. This tubular extension has a sliding fit inthe tubular extension 28 extending from one end of the am plifyingdevice. The extension 28 is in effect a part of an elbow, the otherportion 29 of which has a substantially horizontal axis and is slightlyconical towards its end engaging the remalning portion of the amplifyingdevice. The portion 29 engages the end of a cylindrical tubular portion30 of the amplifying device which tubular portion ends in a disc 31 fromwhich a second tubular portion 32 projects, said portion 32 being oflarger diameten than the tubular portion 30, the axes of the portions29, 30 and 32 being coincident. The tu'bularportion 32, is pivotallysupported on a pivot bolt 34 extending through the end of asupportingbracket 36 which preferably is of cast metal, and of skeletonconstruction to insure rigidity, strength and stability. The bracket 36extends downwardl and obliquely from the pivot bolt 34 an at its otherend a bracing web 37 supporting a post or column 38 whichis drilled'toreceive a vertical supporting rod 39 which has its lower end rigidlysupported by a base 40, which base is rigidly secured to the topboard 40of the machine in any suitable manner as by screws as indicated.

The amplifying means itself, which may i be of wood, fiber, composition,metal or any the follows: tubular portion 41 forms one end of theamplifying means andthis portion is of an external dimension toslidingly fit in the tubular portion 30 of the mounting means; The ri hthand end of the portion 41 as shown in .ig. l isopen and has locatedtherein cross arms 42 to support the right hand end of the rod 43. Theother end of portion 41 which is somewhat longer than the tubularportion 30, is closed by a disc 44 through which the rod 43 projects andwhich forms a second support for the rod 43. The disc 44 constitutes ameans for supporting the inner end of the portion 41 and rod 43 from thesecond tubular portion 45 of the'amplifying means, which portion 45 isof a diameter to enter the portion 32 of the mounting means and is ofsubstantially the length of the portion 32. At its right hand end theportion 45 is secured to a ring 46 which connects with the portion 41thus forming a compartment between the portions 41 and 45 and the disc.44 and ring 46 and in addition the ring 46 reinforces the parts of theamplifying means to hold them in proper position. The left hand end ofthe tubular portion 45 has connected therewith the main casing 47 of theamplifying means which may either be slightly conical asindicated orcylindrical or a combination of both conformations. A ring 48 is securedto the inner surface of the portion 47 at its right hand end and othersimilar rings 49, and 50 aresimilarly secured and placed atsubstantially equal distances between the ring 48 and the open endof-the portion 47. The rings 48, 49, and 50 have relatively largecentral openings of increasing diameter towards the open end of theamplifying means and through these central openings the rod 43 projectsnearly to the free or open end of the amplifying means. The rod 43carries a first disc 51 between the rings 48 and 49, of smaller diameterthan the inner diameter of the portion 47 but of larger diameter thanthe openings in the .rings 48 and 49; between the mm s 49 and 50 itcarries a second disc 52 simi ar to the disc 51 and outside of the ring50 it carries a third similar disc 53.

To permit the sound waves to pass freely through the tubular portion 41and into the right hand end of the amplifying means, a series of holes54 is formed through the wall of the tubular portion 41 between the ring46 and the disc 44 and a second series of holes 55 is formed throu h thedisc 44 between the portion 41 and t e portion 45. As a result of theconstruction described, sound waves porojected into the portion 41 fromthe sound. x are directed through the openings 54, then through theopenings 55 and against the surface of the ring 48, around the inneredge of the ring 48 and against the disc 51 by which they are directedoutwardly recelv'in against the surface of the portion 47 and around theedge of the disc 51 against the ring 49, around the inner edge of thering 49 against the disc 52, outwardlyagainst the portion 47 and aroundthe outer edge of the disc 52 against the ring 50, around the inner edgeof the ring 50 against the disc 53 by which they are directed outwardlyagainst the portion 47 and around the outer edge of the disc 53 to thehearer. The effect of the path traced is that the sound waves set allparts of the amplifying means in vibration corresponding with thevibration of. the sound waves' and the various discs and rings producewhat may be termed reed effects as a result of being free to vibrate attheir edges and having relatively large surfaces and they thus serveeffectively to set in motion an air column of considerable size with theresult that the tone is intensified and given a quality depending uponthe material of which the amplifying means is constructed. By making thediscs and rings and particularly the rod, 43 of wood, a particularlypleasing, mellow and full tone is produced.

-While I have shown my invention in the particular embodiment abovedescribed, it will be understood that I donot limit myself to this exactconstruction as I may employ 95 equivalents known to the art at the timeof the filing of this application without departin from thesco-pe of theappended claims.

at I claim is:

1. A sound chamber for phonographs comprising, an inner tubular portionfor the sound waves, an outer tubular portion encircling said innerportion to provide an intermediate annular chamber, an inturnedimperforate web connecting one end of the outer portion with said innerortion, a partition closing the remote en of said inner portion andextending to and at ,tached to said outer portion, said partition havingpassages connecting with said annular chamber and said inner tubularportion having orifices adjacent to said partition.

2. A sound chamber for phonographs comprising, an inner tubular portionfor receiving the sound waves, an outer tubular portion encircling saidinner portion to provide an intermediate annular chamber, an inturnedimperforate web connecting one end of the outer portion with said innerortion, a partition closing the remote en of said inner portion andextending to and attached to said outer portion, said partition havingpassages connecting with said annular chamber, a secondary partitionarranged in said outer portion in spaced relation to the aforesaidpartition and provided with a central passage, the said inner tubularportion having lateral orifices intermediate its length.

3. A sound chamber for phonographs comprising, an inner tubular portionfor receiving the sound waves, an outer tubular portion encircling saidinner portion to provide an intermediate annular chamber, an inturnedimperforate web connecting one end of the outer portion with said innerportion, a partition closing the remote end-of said inner portion andhaving passages connecting with said annular chamber, said inner tubularportion having orifices communicating with. said annular chamber, andsaid inner portion extending longitudinally beyond said outer portionto' provide a neck for engagement with the outlet end of the tone arm ofthe phonograph.

4. A sound chamber for phonographs comprising, an inner tubular portionfor receiving the sound waves, an outer tubular portion encircling said:inner portion to provide an intermediate annular chamber,

an inturned imperforate web connecting one end of the outer portion withsaid inner portion, a partition closing the remote end of said innerportion and having passages connecting with said annular chamber, a

- secondary partition arranged in said outer portion in spaced relationto the aforesaid partition and provided with a central p'assage, saidinner tubularportion having orifices communicating with said annularchamber, and said inner portion extending longitudinally beyond saidouter portion to providea neck for engagement with the outlet end of thetone arm of a'phonograph.

5. A sound chamber for a phonograph comprising a shell, a rod supportedin said shell adjacent the admission end of said ,shell and extendingunsupported towards the delivery end of said shell, disks carried bysaid rod of smaller diameter than said shell, and flat rings havingcentral clearance openings supported by said shell between said dlsks,said shell being of conicalconformation and said disks and ringsalternating to form a wave-like path for sound waves around the edges ofsaid disks and rings.

In witness whereof, I hereunto subscribe my name this 29th day of April,A. D. 1920. JOHN A. LUNDEN.v

